Dimensional stabilization of wool

ABSTRACT

THE DIMENSIONAL STABILIZATION OF FABRICS CONTAINING KERATIONOUS FIBERS SUCH AS WOOL IS DESCRIBED USING WATERSOLUBLE ISOTHIURONIUM SALTS OF EPHIHALOHYDRIN HOMOPOLYMERS OR COPOLYMERS WITH ONE ANOTHER OR WITH ETHYLENE OXIDE.

United States Patent Ofice 3,694,258 Patented Sept. 26, 1972 3,694,258 DIMENSIONAL STABILIZATION OF WOOL Edwin J. Vandenberg and William D. Willis, Wilmington,

Bel, assignors to Hercules Incorporated, Wilmington,

No Drawing. Continuation-impart of application Ser. No. 872,344, Oct. 29, 1969, now Patent No. 3,594,355. This application Dec. 28, 1970, Ser. No. 102,162

Int. Cl. D06m 3/06; C09d 3/60 US. Cl. 117-141 8 Claims ABSTRACT OF THE DISCLOSURE The dimensional stabilization of fabrics containing keratinous fibers such as wool is described using watersoluble isothiuronium salts of epihalohydrin homopolymers or copolymers with one another or with ethylene oxide.

This application is a continuation-in-part of copending application Ser. No. 872,344, filed Oct. 29, 1969, now US. Patent No. 3,594,355.

This invention relates to keratinous fibers and textile fabrics containing keratinous fibers which have been dimensionally stabilized and more particularly to woolen fabrics having wash and wear characteristics and to a process for producing such fabrics.

It is well known in the textile trade that both woven and knitted woolen fabrics shrink excessively on laundering. This shrinkage varies with the type of weave in the fabric and, in some cases, may run as high as 60% of the original dimensions after machine laundering. Woolen fabrics shrink by two methods; by the so-called relaxation or consolidation phenomenan and by felting. The former is due to the relaxation of tensions introduced during the knitting of weaving operation and is common to all hydrophilic fibers. The latter is due to the unique physical and mechanical properties of keratinous fibers. The physical property which brings about felting is the scaled surface of the fiber which gives it a low coefficient of friction in one direction. This means that when a fabric is subject to mechanical action, the individual fibers migrate in one direction, making for a more dense structure, thereby reducing the linear dimensions. This dense structure is consolidated by the higher resilience of the fibers which is related to their curling or spiraling tendency.

Various treatments such as chlorination treatments, oxidative treatments, alkali treatments and resin treatments have been used to dimensionally stabilize, i.e. reduce the felting shrinkage of wool. None of these treatments, however, has been entirely satisfactory. For example, chlorination treatments require close control of conditions to prevent general loss of the wool-like character of the fabric made therefrom and reduction of wear qualities. Moreover, chlorination treatments generally result in weakening and also impart a harsh hand to the fabric. Oxidative treatments such as with peroxy compounds and permanganate, are likewise difficult to carry out in a manner such as to achieve adequate resistance to shrinkage without undue fiber damage. Resin treatments such as with methylated methylolmelamine and methylated nylon, cause a loss in the subjective properties of the fabric. Such treatments, moreover, require a high temperature cure and a high add-on level to obtain acceptable shrink resistance. This high add-on level causes substantial fabric stiffening and in addition increases the cost.

An object of the present invention is the provision of an improved process for the dimensional stabilization of textile fabrics containing keratinous fibers such as wool.

Another object of the invention is the provision of a durable treatment to provide dimensional stabilization with a low add-on level without weakening or damaging the fabric.

Another object of the invention is the provision of an improved process for dimensional stabilization without discoloring, imparting an undesirable odor or changing the hand of the fabric.

Another object of the invention is the provision of an improved dimensional stabilization treatment which can be applied to the tfibers either before weaving or knitting or after they have been incorporated in a fabric.

A further object of the invention is the provision of an improved process for dimensional stabilization which does not require pretreatment of the fabric, high curing temperatures or the use of organic solvents.

In accordance with this invention, the above and other objects are accomplished by treating keratinous fibers or fabric containing keratinous fibers with certain water soluble isothiuronium salts of epihalohydrin homopolymers or copolymers to be described more fully hereinafter. It has been found that treatment with small amounts of such resins is highly elfective for the dimensional stabilization of textile fabrics containing keratinous fibers such as wool. The said treatment however does not require pretreatment of the keratinous fibers or fabric, high curing temperatures or the use of organic solvents and does not effect color, odor or the hand of the fabric.

The water soluble isothiuronium salts used in accordance with this invention are new compounds described in copending application, Ser. No. 872,844, filed Oct. 29', 1969. Any epihalohydrin homopolymer, copolymer of two or more epihalohydrin, or copolymer of one or more epihalohydrins with ethylene oxide and containing at least 2% by weight of epihalohydrin, having a weight average molecular weight of at least about 50,000 can be converted to a water soluble isothiuronium salt useful in accordance with this invention. These epihalohydrin polymers can be wholly amorphous, partially crystalline, or wholly crystalline. The preparation of such polymers is described in US. Patents such as 2,871,219, 3,135,705, 3,158,580, 3,158,581 and 3,415,761. To produce the water soluble isothiuronium salts used in this invention, the epihalohydrin-ethylene oxide copolymers which have a high ethylene oxide content and hence are water-soluble should contain at least about 2 weight percent of epihalohydrin, whereas those copolymers which have a lower ethylene oxide content and hence are water-insoluble, will preferably contain at least about 30% epihalohydrin. In any case, at least about 5% of the halornethyl groups in the polymer must be converted to isothiuronium salt groups and the product must contain an average of at least about five isothiuronium salt groups per molecule and preferably an average of at least about ten isothiuronium salt groups per molecule.

Any thiourea can be reacted with the epihalohydrin polymer to convert the halo groups to isothiuronium salt groups. Exemplary of the thioureas that can be so reacted are unsubstituted thiourea and mono-, di-, trior tetra-substituted thioureas having the general formula where the Rs can be alike or different and are hydrogen, alkyl, alkenyl, cycloalkyl, cycloalkenyl, aryl, alkaryl, aralkyl or where two Rs taken together are alkylene, as for example, thiourea, methyl thiourea, 1,1-dimethyl thiourea, 1,3-dimethyl thiourea, trimethyl thiourea, tetramethyl thiourea, l-butyl thiourea, 1,3-dibutyl thiourea, l-octyl thiourea, l-stearyl thiourea, l-phenyl thiourea, 1,3-dipheuyl thiourea, l-cyclohexyl thiourea, ethylene 3 thiourea, 4-methyl ethylene thiourea, 4,4-dimethyl ethylene thiourea, 1,3-dimethyl ethylene thiourea, 1,3-diethyl ethylene thiourea, 1 dihydrodicyclopentadienyl-3,3-dimethyl thiourea, l-norbornyl-3,3-dimethyl thiourea and 4 converted to isothiuronium salt groups as determined by sulfur and nitrogen analysis, the RSV of the product and its water-solubility. The polymer product has a M.W. of 100,000 in Examples 1 to 11 and a M.W. of-

1-al1yl-3,3-dimethyl thiourea. Mixtures of the thioureas 5 500,000 in Example 12. The starting copolymer used can also be used in the preparation of the salts. in each case is a 1:1 molar ethylene oxidezepichloro- The amount of the thiourea that is reacted with the hydrin copolymer, having an RSV of 2.2 as measured on epihalohydrin polymer can be varied over a wide range. a 0.1% solution in alpha-chloronaphthalene containing Preferably there is used at least about a excess of 3% acetylacetone at 100 C. (a M.W. of 800,000) in thiourea over the stoichiometric amount required based 10 Controls B and C and Examples 3-11 and an RSV of on the halo content of the polymer, and any amount up 5.7 as measured on a 0.1% solution in alpha-chloronaphto ten-fold or more excess over the stoichiometric thalene containing 3% acetylacetone at 100 C. (a M.W. amount can be used. of 2.7 million) in Control A and Examples 1, 2 and 12.

TABLE I Reaction conditions Isolated product Polymer conc., Temp., Polymer: Percent Example Diluent percent 0. Hrs. thiourea reaction RSV Water solubility 65 72 23:1 2.3 Insoluble 66 72 11 5 0.3 Soluble. s5 72 111 s 0. 29 Do. +90 11 26 0.27 Do. 65 72 1:1 10 0.08 Do. 90 17 1:1 19.4 14.5 Do. 95 8.5 111 33 1.2 Do. 95 24 i=1 73 3.5 Do. 65 9 1:1 31 g {154? Insoluble with 5% N aHSOz. Control 0 65 24 1:1 43 9. .13 Do. 7 95 24 4:1 45 0. 92 42% of total product soluble with a 3. s 95 24 211 so tsgzfor total product soluble with a q 120 1 111 78 a. 1 soiuitie with 3 N81180:!- 1o 95 22 1:1 81 3.7 Soluble with 2% NaHSO 11 99 25 1:1 9 1 3. 5 Soluble with 3% NEHSOE. 12 95 24 1:1 99 5.7 Soluble with 5% NaHSOa.

1 Added LiBr based on weight of thiourea. 2 0.1% solution in DMSO at 25 0. 3 0.1% solution in 0.1 M aqueous K01 containing 5.6% DMSO, at 25 C.

The reaction between the epihalohydrin polymer and EXAMPLE 13 the thiourea can be carried out in solution, in suspension, or in the substantial absence of a liquid reaction diluent as described in copending application, Ser. No. 872,344, filed Oct. 29, 1969.

The following examples will illustrate the process of preparing the isothiuronium salts used in this invention. All parts and percentages are by Weight. The molecular weight of the isothiuronium salt is indicated by the RSV (Reduced Specific Viscosity) determined on a 0.1% solution in 0.1 M aqueous KCl at 25 C., unless otherwise indicated.

EXAMPLES 1-12 In these examples, an ethylene oxideepichlorohydrin copolymer and thiourea are reacted. In Control A and Examples l-6 the reaction is carried out in solution, the starting polymer being dissolved at the given concentration in dimethyl sulfoxide (DM'SO), the thiourea added and the mixture is then heated under nitrogen. In Controls B and C and Examples 7-12 a mixture of the starting polymer and thiourea is blended on a two-roll mill for 10-20 minutes at 160l80 F., adding 1% by Weight of sorbitan monostearate to aid dispersion of the thiourea in the copolymer. The 1:1 by weight mixture is 1.78 times and the 4:1 mixture is 0.45 times the stoichiometric amount of thiourea. The blend is then placed in a reactor, which has an atmosphere of nitrogen, after which the vessel and contents are heated to the specified temperature. At the end of the reaction time, the water-soluble fraction is dissolved, adding sodium bisulfite if necessary to aid in solubilizing the product, the solution is dialyzed by placing it in cellulose dialysis tubing and immersing the sack in distilled water, and after dialysis the water is removed by freeze-drying under vacuum and the product is analyzed. In the case of waterinsoluble products, they are washed several times with water, dried and analyzed.

The reaction conditions are set forth in Table I along with the percent reaction, i.e., percent of chloro groups The procedure described for Example 10 is repeated except that the reaction is carried out in a suspension process by suspending 25 parts of the 1:1 polymer thiourea mixture in 70 parts of n-heptane and then heating the suspension to 95 C. for 22 hours. The product so obtained is reacted (i.e., chloro groups replaced by isothiuronium salt groups), has an RSV of 3.7 and is soluble in water.

EXAMPLES 14-16 These examples illustrate the preparation of isothiuronium salts of other epihalohydrin polymers. The general bulk process procedure described in Example 10 is used in Examples 14 and 15 and the solution procedure described in Example 6 is used in Example 1 6 (using a 10% solution of the polymer in dimethyl sulfoxide). All of the reactions are carried out at C. for 24 hours except Example 16 which is carried out at 65 C. for 20 hours. In Table II are set forth the composition of the polymer reacted, the stoichiometric ratio of thiourea to me halogen content of the polymer, and the properties of the water-soluble polymer so produced. (See Table II in Col. 5).

EXAMPLE 17 Thirty parts of amorphous poly(epichlorohydrin) having an RSV of 1.8 as measured on a 0.1% solution in alpha-chloronaphthalene containing 3% acetylacetone at C. is blended with 32.8 parts of ethylene thiourea (1.2 times the stoichiometric amount) and 0.3 part of sorbitan monostearate on a two-roll mill. The blend is then reacted for 17 hours at C. A 4% solution of the product in water is prepared with 2.5%, based on the Weight of the polymer, of sodium bisulfite. The polymer has an RSV of 1.3 (0.1% solution in 1 M K01 at 25 C.), a M.W. of 100,000, and the percent of chloro groups converted to isothiuronium salt groups as determined by sulfur and nitrogen and analysis is 88%.

TABLE II Reaction Starting polymer conditions, Product stole. ratio Mole thiourea: Reaction Ex. Monomers percent RSV l halogen percent RSV 1 Water solubility My 14 EO/ECH 76/25 4.9 3.1 98 4.0 Souble with 5% NaHSO; 800,000 15 EO/ECH 90/10 4.3 2.9 82 5.0 do 3 16 EO/ECH 75/25 4.9 3. 1 9 0. 42 Soluble 100, 000

1 0.1% solution in a-ehloronapbthalene contsainng 3% acetylacetone at 100 C.

3 0.1% solution in 0.1 M aqueous K01 at 2 3 1 million.

The process of this invention is applicable to any keratinous substrate, including fibers and fabrics made from keratinous fibers or blends or keratinous fibers with other natural fibers including silk, cellulosic fiber and the like, or with synthetic fibers, such as synthetic cellulosic fibers including acetylated cellulose, for example, the cellulose acetates, acetylated rayon and rayon per se; polyamides, particularly nylon, both 6 and 66 types; polyesters, such as polyethylene terephthalate; polyolefins, such as polyethylene, polypropylene and copolymers of polyethylene and polypropylene; acrylic fibers, such as those produced from acrylonitrile and copolymers thereof. Generally a substantial amount of keratinous fibers, for example at least about 25% by weight, will be present in the substrates being treated. The term keratinous fibers as used herein includes sheep wool, mohair, cashmere, camel hair, alpaca, vicuna, angora, and the like.

In carrying out the process of this invention an aqueous solution of the isothiuronium salt of the epihalohydrin polymer is applied to the fibers or fabric in any suitable manner as by dipping, spraying, padding or the like. Any desired or convenient concentration of the aqueous isothiuronium salt solution may be utilized for such application, however, it has been found that concentrations of from about 0.5% to about 15% are quite satisfactory and these, herefore, are preferred. The concentration and time of treatment should be such that the fabric absorbed from about 0.25% to about 10% by weight based on the dry weight of the fabric of the isothiuronium salt of the epihalohydrin polymer. Less than about 0.25% most preferably about 0.5 will not produce the desired dimensional stabilization and more than about 10% offers no particular advantage and, hence, will not normally be used.

After treatment with the isothiuronium salt the fibers or fabric may be dried and then cured at a temperature of from about 95 to 125 C. for a period of from about 10 minutes to about 60 minutes. This short, low temperature cure cycle can easily be handled by ordinary textile processing equipment. While the described temperatures and times are quite advantageous, it will be appreciated that the invention is not limited thereto and that drying and curing may be effected at higher or lower temperatures, i.e., from about 40 C. to about 150 C. with a corresponding decrease or increase in the duration of treatment. The treatment can be carried out under various pH conditions, such as weakly acid, neutral or weakly alkaline. Most preferably, the treatment will be carried out at a pH of from about 6.5 to about 8.

The following examples will serve to illustrate the invention.

EXAMPLE 18 This example illustrates the use of the isothiuronium salt of epichlorohydrin--ethylene oxide prepared in Example 13 as a shrinkproofing agent for a wool fabric.

The fabric used in these tests is a wool flannel. The undialyzed solution of the isothiuronium salt of epichlorohydrinethylene oxide in water prepared in Example 13 is diluted with water to concentrations of 1.5% and 3% by weight of the polymer (the solution also containing 0.7 and 1.5%, respectively, of unreacted thiourea) and the acidity is adjusted to a pH of 7.3. In each case, 0.05%

based on the Weight of the solution of a commercial wetting agent is added.

Two lengths of the fabric are pretreated, one by pad ding with 2% aqueous sodium bisulfite, rinsing and drying, and another by padding with a 1.5% aqueous solution of sodium dichloroisocyanurate, containing the same amount of the wetting agent, then after 1.5 minutes passing the fabric through a 2% aqueous sodium bisulfite solution, rinsing and drying.

Swatches of the pretreated fabric and a fabric with no pretreatment are then saturated with the isothiuronium salt solution for one minute, squeezed through the rolls of the padding machine and after weighing to determine the solution pick-up, the swatches are dried and cured by heating in a vented circulating air oven at 107 C. for 15 minutes. The treated swatches along with swatches of the untreated fabric and the two pretreated fabrics are relaxed by soaking for 15 minutes and then rotating for five minutes in a cube-shaped washing machine, charged with 25 liters of 41 C. water containing 200 g. Na HP0 112.5 g. NaH PO and 12.5 ml. of the wetting agent, after which the swatches are rinsed and dried. Each of the swatches is then subjected, first to a mild felting test (tumbling in 25 liters of a solution containing 200 g. Na HPO and 112.5 g. NaH PO for sixty minutes at 41 C. rinsed with water and dried) and then, after measuring to a severe felting test (tumbling in 12.5 liters of the same sodium acid phosphate solution for 45 minutes at 41 C. and again rinsed and dried). The percentage shrinkage is then measured for each swatch. Tabulated below is the percent felting for each swatch, together with controls run at the same time with no shrinkproofing agent.

The above test results show that the epihalohydrin polymer isothiuronium salt is not only an effective shrinkproofing agent, but can even be used without fabric pretreatment.

EXAMPLE 19 This example illustrates the use of the thiuronium salt produced in Examples 14, 15, 16 and 17 as shrinkproofing agents on various types of woolen fabrics.

Severe felting tests are carried out as described in Example 18. The aqueous resin solutions are adjusted to a pH of 8 in the tests made on resins of Examples 14, 15 and 17 and to a pH of 3.5 in a test on the resin of Example 16. The resin solutions are applied to the woolens by padding (without pretreatment) and after the relaxation procedure, the severe felting test is run through three full complete cycles. Tabulated below is the percent shrinkage given on a cumulative basis compared with controls where the woolen received no treatment.

8 (1) treating the keratinous fibers with a small amount of at least one water-soluble isothiuronium salt .of an epihalohydrin polymer wherein at least about 5% of Percent area shrinkage Cure con- Isothiuronium Percent ditions, First Second Third Example salt add-on min./ 0. Wash wash wash Test on wool flannel 19 Control 29 4o 47 3' igiltii 8 3 Test on worsted Wool flannel 19 Control 2 4 nug fi 48 6'1 62 4: 1 30/120 0 0 1 Ex. 15 1. 30/120 0 3 7 Ex. 16 3. 5 /120 0 1 6 Test on wool knit 19 2 2 st 1'26 ii 4i 7 30 120 7 7 7 Ex. 16 3. 5 15/120 0 10 26 Test on worsted knit 19 Control 0 65 70 x. 14 4. 4 30/120 4 6 9 EXAMPLES -23 These examples illustrate the use of various isothiuronium salts as shrinkproofing agents to dimensionally stabilize wool flannel. Samples of an ethylene oxideepichlorohydrin copolymer containing monomers in a mole ratio of approximately 75/25 are reacted with trimethyl thiourea, ethylene thiourea, l-phenyl thiourea and 1 dihydrodicyclopentadienyl 3,3 dimethyl thiourea as described in Example 14. A 3% by weight aqueous solution of each isothiuronium salt is adjusted to a pH of 7.5 and then used to treat a swatch of wool flannel as described in Example 18. The isothiuronium salt treatment does not change the color or effect substantially the hand of the fabric swatches treated. The treated swatches along with swatches of the untreated fabric are relaxed by soaking in sodium acid phosphate solution as described in Example 18. After rinsing and drying, each of the swatches is subjected to mild and then severe felting tests. The control swatches shrink approximately 27% during the mild felting test and 56% during the severe felting test. The swatches treated with the various isothiuronium salts exhibit substantially no shrinkage as a result of the mild felting test and only minor shrinkage as the result of the severe felting test.

EXAMPLE 24 This example illustrates the use of the isothiuronium salt of Example 15 to treat wool fibers.

Australian 64s worsted sliver is run through a pad containing a 2% by weight aqueous solution of the isothiuronium salt described in Example 15 adjusted to a pH of 8.0. The percent add-on is approximately 2.5. The resulting treated worsted sliver is cured at a temperature of 120 C. for 15 minutes, spun into yarn and woven into worsted wool flannel. Swatches of the fabric prepared from the treated worsted sliver and also control swatches prepared from untreated worsted sliver are relaxed as described in Example 18. After rinsing and drying each swatch is then subjected to a mild felting test and severe felting test as described in Example 18. Shrinkage in the control sample is approximately 48% in the mild felting test and 61% in the severe felting test. Shrinkage in the fabric prepared from treated fibers is essentially nil in both the mild and severe felting test.

What we claim and desire to protect by Letters Patent is:

1. A process of dimensionally stabilizing fabrics containing at least some keratinous fibers comprising:

the halo groups of the epihalohydrin polymer have been substituted by isothiuronium hydrohalide groups, said isothiuronium hydrohalide groups having the formula (R)zN(!l=N(R)z*X- where each R is selected from the group consisting of H, alkyl, alkenyl, cycloalkyl, cycloalkenyl, aryl, alkaryl and aralkyl or together with a second R is alkylene, and xis a halide ion, said epihalohydrin polymer being a homopolymer of an epihalohydrin, a copolymer of at least two epihalohydrins or a copolymer of at least one epihalohydrin and ethylene oxide, and (2) heating at an elevated temperature to cure the isothiuronium salt of epihalohydrin polymer.

2. The process of claim 1 wherein the keratinous fibers are treated after they have been incorporated in a fabric.

3. The process of claim 1 wherein the keratinous fibers are treated before they have been incorporated in a fabric.

4. The process of claim 1 wherein the isothiuronium salt of an epihalohydrin polymer is the thiourea salt of poly (epichlorohydrin) 5. The process of claim 1 wherein the isothiuronium salt of an epihalohydrin polymer is the thiourea salt of an ethylene oxide-epichlorohydrin copolymer.

6. The process of claim 5 wherein the ethylene oxideepichlorohydrin copolymer contains at least 75 mole percent of groups derived from ethylene oxide.

7. Keratinous fibers treated with from about 0.25% to about 10% by weight of a cured isothiuronium salt of an epihalohydrin polymer wherein at least about 5% of the halo groups of the epihalohydrin polymer have been substituted by isothiuronium hydrohalide groups, said isothiuronium hydrohalide groups having the formula where each R is selected from the group consisting of H, alkyl, alkenyl, cycloalkyl, cycloalkenyl; aryl, alkaryl and aralkyl or together with a second R is alkylene, and xis a halide ion, said epihalohydrin polymer being a homopolymer of an epihalohydrin, a copolymer of at least two epihalohydrins or a copolymer of at least one epihalohydrin and ethylene oxide.

8. A dimensionally stabilized fabric containing at least some keratinous fibers treated with from about 0.25% to 9 about 10% by weight, based on the weight of the keratinous fibers, of a cured isothiuronium salt of an epihalohydrin polymer wherein at least about 5% of the halo groups of the epihalohydrin polymer have been substituted by isothiuronium hydrohalide groups, said isothiuronium hydrohalide groups having the formula where each R is selected from the group consisting of H, alkyl, alkenyl, cycloalkyl, cycloalkenyl, aryl, alkaryl and aralkyl or together with a second R is alkylene, and X'- is a halide ion, said epihalohydrin polymer being a homopolymer of an epihalohydrin, a copolymer of at least two epihalohydrins or a copolymer of at least one epihalohydrin and ethylene oxide.

References Cited UNITED STATES PATENTS 12/1968 Breslow 26079.1 X 10/ 1969 Vandenberg et a1. ..26079 X 7/1955 Greenlee 117-161 X 1/1=962 Schroeder 117141 X 1/ 1971 Porret et a1. 117161 X 12/1957 Pardo 117--141 4/1963 Gagliardi et a1. 117-141 X WILLIAM D. MARTIN, Primary Examiner H. I. GWINNELL, Assistant Examiner US. Cl. X.R.

117-161UZ, 161 UA, 161 UN j UNITED STATES PATENTOFFICE JCERTI ICA COR ECTION 3 Edw in Jlifahdenberg It is c ertified that error appears. in the boire-idntifid patent: and; that said Letters 'Patent'gr e'. hereby cor re cted as shown below Colqf p .p.; Table I," Example flll, under Temp. 9C.

99" should're'ad- "95-! CQI. 4 bf p.p.-; Table I, under WatepSolfibli-lity XL Q" "%Na-HSO3" should read "'5%NaI'-ISO3".

Signed" and sald this lst'd ajy May 1973. I

hit-3:313:

1i; i' L5JTL'JHI'Jl1," JR. Y ROBERT GOTTSCHALK i 1v "'LlJ flttcsting Officer C oimmissioner'of Patents 

